Thread: Naniwa 12000 ruined?

I have a naniwa 12000, had it for about 2 years and still razors nicely but it has developed stains and smells like mildew. I treat all my stones the same, use them, wipe them off, let them dry and then store them in a plastic container in the plastic bubble sleeves they came in. This is the only one that has this problem. Is this infact mildew from not letting it dry completely or storing it in the box?